Process for the continuous production of dry hydrochloric acid and potassium bisulfate from potassium chlorid and sulfuric acid.



T. MEYER & A. KLAGES. PROCE$S FOR THE commuons PRODUCTION OF DRY HYDROCHLORIO ACID AND POTASSIUM BISULFATE FROM POTASSIUM CHLORID AND SULFURIC ACID.

APPLICATION FILED JAN. 6. 1013.

Patented June 9,1914.

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TIHEOIIOR MEYER, OF OFFENBACH, AND AUGUST KLAGES, 0F MAGDEBURG, GERMANY.

PROCESS FOR THE CONTINUOUS PRODUCTION OF DRY HYDROCHLORIC ACID AND POTASSIUM BISULFATE FROM POTASSIUM CHLOIil'ID AND SULFURIC ACID.

LGQEBALML.

Specification of Letters Patent.

Patented June 0 101 at.

Application filed January 6, 1913. serial No. 740,4t63.

To all whom it may concern:

Be it known that we, THEODOR MEYER and AUeUsr KLAens, both subjects of the Elm peror of Germany, and residents the first of @fienbach, in the Grand Duchy of Hesse,

fate from potassium chlorid and sulfuric acid it is necessary to previously produce good potassium bisulfate. This salt cannot be produced by the pan process which is generally applied for the production of sul fate of sodium and the reason therefor is that the decomposition of the potassium chlorid by sulfuric acid is more diflicult than the decomposition of sodium chlorid and further that a volatilization of the sulfuric acid or of the potassium chlorid easily occurs if the temperature exceeds a determined degree. The application of the pan process for this purpose would however be possible if the potassium bisulfate formed at 300 C. a thinly liquid mass. The properties of hot liquid potassium bisulfatc produced at a temperature of about 300 were however not known as this substance had never been prepared.

Uur experiments have shown that the potassium bisulfate forms at 300 C. a mass which is as liquid as water and which can be drawn 0E without coagulating. It has further been discovered that the potassium chloridis completely transformed in the retort and that in this manner the preparation of potassium bisulfate can be effected without the inconveniences of the pan process.

'llhe construction'of the retort is of importance. litetorts of cast iron are not very practical; the retort has to be lined with an acid proof chamotte material in order to insure a continuous and uniform working without deterioration of the retort or of the product. llf bisulfate of sodium is to be used instead of potassium bisulfate the retort must be similarly constructed' It is further advantageous .to effect the chemical transformatio p-as far as possible upon the surface of the hot'liqnid molten potassium bisulfate by pouring into the retort, which is filled up to the middle of its height with hot liquid potassium bisulfate, potassium chlorid and sulfuric acid, the latter being of about 80 to 90% Ill S0 liven if sulfuric acid of about 90% is used the action of the reagents upon the cast iron of the retort is still very small.

During the process an active decomposition of the potassium chlorid takes place and the hot liquid potassium bisulfatc is continuously drawn off as close as possible at the bottom of the retort at a temperature of 300. The potassium bisulfate thus obtained forms an easily coagulating and brittle salt which is scarcely hydroscopic and much easier ground than the sulfate of sodium. Its percentage of sulfuric acid can easily be maintained at between 24. to 26% in the accompanying drawings the way this improved process is carried out is illus trated.

The apparatus consists of a large retort a into which the potassium bisulfate is poured through a funnel 7) fined in the lid of the retort. if the retort a is heated from the furnace e the bisulfate begins slowly to melt and it is heated up to about 300 of temperature. if the liquid. bisulfate has reached this temperature the potassium chlorid is introduced into the retort through the funnel b and the sulfuric acid through the pipe 0 which is also fixed in the lid of the retort. 'lhesc two products are allowed to flow in continuously. The gases escape through the outflow pipe (Z mounted in the lid of the retort and the bisulfate is drawn oil the retort through the inclined outiiow tube f, the open lower end of which is situated on the bottom of the retort its outer end projecting through the side wall. of said retort. The level of the molten bisulfate must be maintained at such a height that part of the bisulfate can freely flow out through the overflow pipe W e claim Process for the continuous production of dry hydrochloric acid and potassium bisulfate from potassium chlorid and sulfuric acid consisting in introducing into a large retort potassium bisulfate, in heating it to a temperature which is high enough to transform the potassium bisulfate into a liquid substance, in introducing into the [retort potassium chlorid and sulfuric acid, in main- In witness whereof We have hereunto set taining the temperature at such a degree our hands in the presence of two witnesses.

that the bisulfate ofpotassium remains liquid in order to insure that the transfor- 5 mation of the potassium chlorid and sulfuric acid takes place on the surface of the liquid bisulfate and in drawing ofi continuously the heavy bisulfate which settles on the bottom of the retort, substantially as described 10 and for the purpose set forth.

THEODOR MEYER. AUGUST KLAGES. Witnesses as to Theodor Meyer:

J EAN GRUND, ELSE MEBUS. Witnesses as to August Klages:

E. KOSTENBADER', JOHANN'ES GRoTE. 

